Boil or steam the potatoes until they are cooked. In a meantime make the bechamel sauce. Warm the milk in one saucepan, but do not bring it to boil. In another saucepan on low heat, melt the butter until it starts to foam. Add the flour and with constant stir cook it for 3-4 minutes or until the flour is lightly yellow. Than add the warm milk and whisk it with wire whisk so thatthe sauce remains smooth and without lumps. Cook it for 10 minutes on low constantly stirring. Then add the potatoes, garlic, salt, pepper, nutmeg and cook it for another 5 minutes. If the sauce is too thick, add some water.Bon appetit :-)